enter in bios with the file copied into a usb flash drive
you must have a ups so if electricity decides to leave your house, your pc will finish the bios upgrade perfectly
enter in bios select upgrade bios, point it to the file and leave it do the process
once it finishes, turn off pc, unplug pc, remove heatsink, put the new cpu, don't bend pins on it, lock it in place, put the new heatsink with the thermal paste it comes, connect the fan and reconnect the psu to turn it on, that should be all
btw, from where did you got the bios file you want to use?